Manufacture of screw-blanks



' {No Model.)

H. ONES.

MANUPAGTU SCREW BLANKS.

No. 533,599." Patented Feb. 5, 1895.

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PATENT HORACE K. JONES, OF HARTFORD, ASSIGNOR TO THE RUSSELL d: ERVVIN COMPANY, OF NEW BRITAIN, CONNECTICUT.

MAN U FACTU RE OF SCREW-ELAN KS.

SPECIFICATION forming part of Letters Patent No. 583,599, dated February 5, 1895.

Application fi d May Q, 1893. Serial N0.473,580- (No model.)

To asZZ whom it may concern.-

Be it known that I, HORACE K. J ONES, a citizen of the United States, residing at- Hartford, in the county of Hartford and State of Connecticut, have invented certain new and useful Improvements in the lllanufacture of Screw-Blanks, of which the following is a specification.

My invention relates to improvements in the manufacture of screw blanks, and the chief objects of myimprovement are economy in production and theproduction ofa superior article.

In the accompanying drawings: Figure 1 is a side elevation of a blank showing the result of the first step in the process of manufacture. Fig. 2 is a plan view of the same. Fig. 3 is a longitudinal section of the same on the line as a; of Fig. 2. Fig. 4e is a side elevation of the complete blank. Fig. 5 is a longitudinal section of the same on the line 3 y. Fig. 6 is a plan view of a blank showing the result of the first step in the process of manufacture in a slightly difierent form from that first illustrated. Fig. 7 is a sectional view of the same on the line .2 2. Fig. 8 is a corresponding View in still another form. Fig. 9 is a plan View of a blank for a machine screw or bolt showing the result of the first step in the process of making such blanks. Fig. 10 is a longitudinal section thereof in a plane extending at right angles to the slot, and Fig. 11 is a longitudinal section of the finished blank on the line of its slot.

I first head the blank in any ordinary heading machine within a suitable die and at the same time swage a slot or nick 9 in the face of the head, said slot terminating a little short of the full diameter of the head so as to form a slot with closed ends. I next place the headed blank thus formed in any ordinary shaving machine to shave or trim the head, thereby cutting off the metal at the ends of the slot and leaving the head perfectly true and round, changing the metal from the form shown in Figs. 1, 2 and 3 to that shown in Figs. 4 and 5. I prefer to form the slot 9 in a die which is slotted transversely in alignment with that part of the header which forms the slot, whereby offsets 10 are formed or thrown out on each side and form the closed end of the slot in the first blank. A die thus slotted is mentioned in my Patent No. 335,131, issued February 2, 1886. A slot 9 with inclosed ends may however, be formed in a die g 5 having no such slot in its face. For example, instead of making a round cavity for forming a round head in the die, the cavity for the head may be made slightly oval to receive an excess of metal on the sides which come opposite the ends of the slot and thereby leave a solid wall 11 at each end of the slot 9 as shown in Figs. 6 and 7. I am thus enabled to make the slot of a length a little in excess of the diameter of the finished head as illustrated in Fig. 6 in which the broken circle 12 indicates what may be the size of the head in the finished blank. The projecting portions 11 of this head may slant from the outer end to the base of the head as shown in Fig. 7. Instead of an oval die for forming the oval head, a die with a round cavity for forming a round head may be made so as to form a head slightly larger than the head of the finished blank and leave the transverse walls at each end of the slot. Such a head may slant from the top to a point just below the bottom of the slot 9 as illustrated by the end walls of the slot 13 in Fig. 8. These slight variations in the result of the first step in my process show that the precise form of the blank in all particulars is not essential, the essential feature being that the headed blank is provided with a swaged nick or slot which is inclosed at its ends and is of such form that the ends of the slots will be dressed off in finishing or shaving the head. Other changes of a like nature to those suggestedin this preliminary blank will readily suggest themselves to skilled mechanics, and may be employed without departing from my invention.

Solid heading dies and those which are made in two parts and are opened to discharge the blank are both well known and either kind of die may be used in the practice of my process. I prefer to employ the open or divided heading die because blanks can be more speedily formed therein and inasmuch as my process requires the heads to be dressed or shaved, such fin as may be thrown out at the division or seam of said dies will be dressed ed in the final step of my process so that there is no objection to the use of the open dies.

While I have described my invention as an improvement in the manufacture of screw blanks it is evident that there would be no departure therefrom if the blank should be made into a bolt instead of a screw or if the same process should be employed for producing cylindrical heads or heads having a square shoulder or under face instead of a beveled one, thereby making a blank for a machine in Fig. 11 and the circle of broken lines in Fig. 9 indicates the size of the said finished head. I have shown this head as having a flat top but it maybe convex if desired. The beveled portion 1a as well as the offsets 10 will be removed in the shaving or finishing of the head thus opening the ends of the slot 9.

By my improvements I am enabled to swage the slot simultaneously with forming the head, thereby producing at a small cost a head having a slot witha firm and tough surface while at the same time by dressing off the ends of the slot and head, I produce a neatly finished head and one that is true and round, whereby my process is specially adapted for making blanks for machine screws and bolts.

I claim as my invention- That improvement in the manufacture of screw blanks having slotted heads, which consists of first swaging the head and slot, and at the same time forcing the metal from the swaged slot outwardly to form projections extending beyond the diameter of the head in the finished blank from the top of the head opposite the slot, down the tapering sides of the head to or below the bottom of the slot, and then opening the ends of the slot by dressing the sides of the heads, substantially as described and for the purpose specified.

HORACE K. JONES.

Witnesses:

THEO. E. SMITH, M. S. WIARD. 

